Fast, variable system delay correction for spiral MRI

Magn Reson Med. 2014 Feb;71(2):773-82. doi: 10.1002/mrm.24730.

Abstract

Purpose: Time-varying system delays and eddy currents can substantially reduce the image quality of spiral images. A new method is proposed to estimate variable system delays for spiral-based trajectories.

Methods: This approach requires a minor modification of a conventional stack-of-spirals sequence and analyzes data collected on three overlapping orthogonal cylinders.

Results: Initial results are presented for acquired and synthesized phantom data and in vivo data.

Conclusion: The proposed method includes gradient coupling effects, requires no phantom measurements or specialized hardware, is robust to off-resonance effects, and estimates independent continuous delays for each gradient channel over the data-sampling period.

MeSH terms

  • Algorithms*
  • Artifacts*
  • Brain / anatomy & histology*
  • Humans
  • Image Enhancement / methods*
  • Image Interpretation, Computer-Assisted / methods*
  • Magnetic Resonance Imaging / methods*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Signal Processing, Computer-Assisted